What? Are you implying that you don't think anyone should take action to prevent something that is merely "likely" as opposed to certain?

If so, fair enough. Personally I care about leaving a decent world for others to live in, so I think that even a 50% "likelihood" that we're responsible for things like this is grounds for action.

I also think, as the real liklihood rises toward 100% (it will never quite get there - science doesn't work like that), that those demanding total certainty before they'll support any action are being selfish and irresponsible in the extreme.)

It likely that you are a reasonably intelligent human being and just as likely that your views are sincerely held, but to pretend that in science that a likely qualifier may be appropriately applied is more likely just trolling.

Likely. You are in the land of it. Like it or lump it.

When I studied probability and statistics (I am an Operation Research scientist) the term "likelihood" was a well accepted "scientific term".

The IPCC defines these sorts of terms fairly carefully.

I'm not sure that the authors here have used the same definition but the IPCC defines "likely" as a probability of occurrence of no less than 66 per cent.

www.ipcc.ch/pdf/supporting-material/uncertainty-guidance-note.pdf

I can understand a statement about Black Caviar's chance of winning his next race as being above 66 per cent.
Black Caviar repeats a similar but not identical event. On 22 occasions the result has been the same.
The statements in this article bear more than a passing similarity to pronouncements made in women's magazines horoscopes, or psychic readings on the radio by self-proclaimed psychic gurus.
Unless scientists can make more reliable predictions, or at least not make dodgy predictions, they have no more moral authority than plausible charlatans.

I can't understand why you assert that it is likely that I am a reasonably intelligent human being, without adducing evidence in support of this hypothesis.
Even my children are taught that for each statement they make in HSC essays, they should have at least one following item of evidence.

For the information of readers, Jess Beckerling is an anti-logging campaigner who has started studying at Murdoch University for what I assume is a science degree. My view is that, unless she can provide references and links to the science behind her claims, she should be viewed as just another greenie who is opposed to native forest logging on emotional and/or philosophical rather than conservation grounds. Nothing wrong with that, of course, but emotion and philosophical beliefs will help very little in working out and applying the actions needed to prevent further forest collapse from climate change.

I can give you all the evidence you could ever want Bernie, but I'm sure you have just as ready access to it as I do. The need to protect native forests is based on logic, it is also an emotional and philosophical issue, of course it is. If it wasn't there'd be something wrong with us.
I'm not sure what you'd like me to substantiate. There is no dispute with any of what I've said as far as I'm aware - spreading dieback, poisoning marri, ForestCheck not covering the karri or many threatened species - but I can give you ample evidence on them all if you so desire.
There are obvious, rational links between forest collapse from climate change and continued clearfelling and intensive logging of native forests. Presumably what we all want is the maintenance of healthy functioning ecosystems able to support south west biodiversity. Logging is helping to destroy these and needs to be stopped.

Jess, in your first comment, you claimed the following adverse environmental impacts from logging:
1. turning a "healthy forest," into an unhealthy one
2. "logging is spreading Phytophthora"
3. "ForestCheck.....is being used by industry representatives who are making outrageously inaccurate claims such as that they now have proof that logging has no impact on any species or on biodiversity as a whole."
4. "an industry that is costing us.... possibly even our ..... numbats and who knows what else"
Can you please provide just 1 or 2 science-based links to each of these 4 claims to substantiate them?

You further state that "native forest logging (is) an industry that is costing us money". This is a well-used but largely irrelevant statement that ignores the fact that very few government undertakings actually make a profit for the people of WA. No one is suggesting that the Departments of Health or Police or Education make us a profit, so why should the Forests Products Commission and/or DEC be any different?

The most important logical conclusion that I draw after my 30+ years of involvement in forest issues is that successive governments have failed to fully fund the DEC to properly manage our forests. This trend was exacerbated by the Gallop government's decision in 2001 to end logging of old growth forests and declare an extra 35 national parks in the SW forests but provide no money to manage these areas and the many human and natural impacts which are degrading them.

WOW Bernie, I'm stunned that you'd say that the fact that logging costs us money is irrelevant, and that you seek to compare FPC to the dept of Health, Police or Education - which all give us something very valuable. The FPC logs our native forests and has effectively shut down its farm forestry sector.
72% of the karri FPC logs goes straight to the woodchip mill, and 60% of the jarrah is burnt as firewood or charcoal. The benefits to us of leaving the forests standing far outweigh the benefit from the small amount of useful timber it generates. If it can't even make a profit why on earth do we allow it continue?

As far as the dotpoints go, here is a start off the top of my head;
1) Turning a healthy forest into an unhealthy one - this can be looked at in terms of either the timber sourced from regrowth areas or the ecosystem function, both are substandard compared to areas that have never been logged or were lightly selectively logged. Ample evidence of the former from a sawmilling point of view - for example see Auswest MD Gary Addison's statements when negotiating purchase of Gunns' contract. On the latter, evidence includes the fact that regrowth karri is rife with armillaria and other wood rotting fungi. See DEC chief pathologist's work on this. Clearfelling is not good for forest health, neither is intensive logging of jarrah forests. Surely that's obvious. The age structure is significantly altered among other things. Lindenmayer, Calver, Wardell Johnson and many others have written on this.

2) Spreads dieback - for most recent see Conservation Commission's End of Term Audit of the Forest Management Plan. DEC documents the FPC breaches it has investigated since the beginning of the FMP, many of them concern the spreading of dieback. I'm sure you're aware of this.

3) John Clarke on ABC rural report 16th May, he said we now have 'proof' that logging has no impact on wildlife or biodiversity - which is plainly untrue.

4) not one single study has ever been done on the effects of logging on numbats, http://www.parliament.wa.gov.au/parliament/pquest.nsf/969994fcf861850d4825718d002fe7fb/fb3178d6a7cdf636482579ce00271310?OpenDocument fewer than 1000 of them remain in the wild and we're still destroying their last refuges with intensive logging operations.

What interests me is why do you want it to continue?

Gil, there's little doubt that large parts of our south west forest estate is in poor condition. However, I have to disagree with one of your claims, namely "impenetrable to humans until the cattle got in there and knocked out the undergrowth". If you read the journals and diaries of the early explorers and settlers, this statement is simply not correct as it applies to our forests. Certainly, our coastal heath was almost impenetrable but much of our forest was subjected to 3 to 4 year summer or autumn burning by Aborigines (see Hallam 1975: Fire and Hearth or I can send you a copy of an excellent speech she gave in 2002). Their fire regime created forested landscapes that were mostly open, easily traversed on foot or by horse and containing large mature trees. It was the withdrawal of Aboriginal fire regimes and logging that was not followed up by appropriate silvicultural management of the logged forests that did the initial damage, including allowing dense shrubby regrowth to replace the open understorey.

It's not too late - in fact, it's never too late - to turn this situation around but it requires people to understand the science of forest management and apply their knowledge to manage the many threats and correct the lack of silvicultural practices during the first 80 to 100 years of European settlement in WA. In turn, this will never happen unless governments provide adequate funding but the environment is now far less important to the people of WA than it was pre-GFC and it's a rare government that actually leads rather than follows public opinion.

WOW ! What a statement, Bernie despite your claims of our forrests 'not being impenatrible' clearly, you need to do some more serious study on the issue.
I would suggest a good source of reading would be the publication
Group Settlement Part 1, by J.P. Gabbedy published by W.A. University Press.
This publication describes very clearly, how thick our forrests were, and that was much later then mentioned in your writtings. So if it has been reported as thick in that time, clearly, it must have been far thicker back in the times you refer too ?
Also, as a resident of Kalgoorlie for many years, I can attest to many tree stumps around Kalgoorlie that three men could not put their arms around.
Again, a fact that woul d substantiate considerble forrest throughout this state in the early days, not just the S.W. as claimed.
Moreover, it would seem very little attention is focused on what sustained W.A.'s development prior to the discovery of precious minerals.
W.A.'s mainstay was farming, sheep, beef, dairy being the major sustainers, then the TIMBER industry became the first resource to be raped from our land. I'd respectfully suggest you do a little research into that matter, specificaly beginning from Augusta in our furtherest South West, ask yourself why railways were built down that way, and why wharves were also built and what was exported in major tonnages from said wharves.
Slowly the cutting industry came up the coats working it's way up, decimating our forrest on the way until WW 1, when the manpower was stolen from the timber companies to wage war. After WW 1, it never really recovered to the levels it once was, visit some of the South West towns and peruse the records there, of the amounts of timber that was taken out, these do not lie.The timber industry receded and WW 2 was a major incurson to the industry, and by this time, much of our mineral resources had come on stream and were easily taking up the slack of the workers, though timber was still an industry though a shadow of it's former self.
Then came Bauxite and what a curse that was for our forrests, not only the direct attack against the timber, but also by the diseases spread by the mining activeties themselves. I won't go into the inappropoiate replanting of non indigenous trees, and the effects of same on our ecology, that's another entirely different subject, suffice to say, it's impact will be evident for many generations.
Then came wood chips, where trees were indiscrimanently cut and chipped, funny thing, no one ever complaine dof the destruction of our fauna with these activeties, nowadays we see and hear of much handwringing and how we're supposed to save them all, yet once we deliberately, willingly turned the othet cheek to their destruction via the destruction of their habitat.
I have to laugh at your claims of "science of forest management and apply their knowledge to manage the many threats and correct the lack of silvicultural practices during the first 80 to 100 years of European settlement in WA." Really, it's total joke to read self patronising crap like that.
I have seen, and been INVOLVED with that hypocrisy, specifcaly the combating of Dieback.
Where along the Bibbulman track, the D.E.T. has established foot baths to disinfect boots traversing the track. In all the years I've been involved on maintenance of said track, I've only seen these baths contain a sterilizing solution ONCE, and that was when "I" supplied it myself.
Every other such bath, anywhere along the track, has never contained any such solution despite signs from D.E.T. claiming they do.
Ergo ? their claims of fighting this scrouge are a LIE.
In closing, I'd like to point out, the onus to save our forrest, does not simply lie with our Govts, it lies with each and everyone of us, including the mining companies and our toothless E.P.A. which in my 62 years I have yet to see serious factual evidance they are doing what they've been assigne to do.

Murray, there's an on-going debate about whether it was hunting by Aboriginal people or their use of fire which caused the loss of the mega-fauna. Nonetheless, whatever the cause, the changes to Australia's vegetation starting some 50,000 years ago were profound. The next major change was when Europeans moved in from 1788 onwards, ultimately causing Aboriginal burning regimes to be changed or completely removed from the landscape. In turn, the resulting environmental changes may, as you suggest, now be causing further changes at the same time as climate change is also impacting upon the Australian landscape.

Bernie and Murray
Further to your reference to the loss of regular Aboriginal burning, is the recent research from SE NSW and elsewhere showing that a lack of fire results in eucalypt decline and eventual death. As today's managed prescribed burning cannot hope to keep up with the natural pre-European burning regime by Aboriginals and lightning, this factor is becoming apparent as we now have far less fire in the landscape.

The otherside of the coin is that because we have less fire fuels build to unnatuarlly high levels and eventually they do burn in hot summer bushfires of unnatural intensity thereby doing far more environmental damage than would naturally have been the case.

Yes, man has much to answer for regarding land management problems but the readiness of some scientists to disregard this in favour of strengthening the case for climate change says much about ideological agendas amongst our academic community.

Bernie, I am aware that there was an argument over the sequence of events that led to the mega-fauna extinction. But it seems that the authors of the paper I referenced above, have a detailed climate-megafauna-fire record, and concluded that the sequence went: megafauna here; people arrive; megafauna disappear; fire increases. The previous arguments I read about whether it was fire or climate change, relied on large ranges in estimates of the dates of various events, which led to uncertainty in determining the sequence. The authors of this latest study are of the opinion that this question is now answered.

Murray, the article you referred to in your earlier post states: "Our results suggest that human arrival rather than climate caused megafaunal extinction, which then triggered replacement of mixed rainforest by sclerophyll vegetation through a combination of direct effects on vegetation of relaxed herbivore pressure and increased fire in the landscape." The abstract doesn't explicitly state that the changed fire regimes only occurred after the loss of the megafauna..

In other words, the sequence could have been:
megafauna here; people arrive; changes to fire regimes, megafauna disappear; fire increases.

As difficult (or strange) as it may seem, I have tried to mentally put myself into the shoes of the first Aboriginals at the time of their first arrival here and ask myself what would they have eaten in the first few hundred or thousand years of their colonisation. They would have found large volumes of animal protein in the form of the megafauna, similar to pre-European Africans who ate (and still eat) large volumes of plant material, even though there were (and still are) many large edible animals in Africa. The big difference between the two continents is that, by use of fire, Africa's large animals thrived on the resulting grassed plains, while Australia's large animals died out, partly because they were hunted (as they were/are in Africa) but also because they weren't grass eaters.

Overall, therefore, I find it easier to conclude that the first Aboriginals caused the loss of our megafauna because of the new fire regime they had imposed which they'd applied so as to maximise the production of edible plant material, while at the same time hunting fauna for the occasional meat feast.

If there are any flaws in my thinking, feel free to point them out as I'd welcome greater clarity in our understanding of fire and its use by Aborigines.

Bernie,

The full paper is more detailed than the abstract.

When I studied biogeography at university (which was 25 years ago now) it appeared that when humans arrived on a new continent, mega-faunal extinctions happened around the same time, though the accuracy of time estimates had large errors - which is an uncertainty that contributes to the arguments around cause.

Europe, North and South America also had megafauna extinction. The Rule etal paper claims to analyse a more accurate timeline for Australia.

The argument goes that African megafauna did not suffer extinction as a result of human arrival - because humans did not 'arrive'. Humans were not an 'introduced species' in Africa. Humanity and the African megafauna evolved together over what really are incomprehensible periods of time. The megafauna in the new continents, in contrast, had no defence against humans.

Have you read 'The Future Eaters' by Tim Flannery? - it expands upon this theory.

I don't have references to quote on this point but I understand that Europeans arriving in North America nearly wiped out buffola through hunting. And the Moari ate several species of Moa to extinction in NZ - the largest species went first.